Tristimulus: Color Lab

iOS app by Shadowfetch · App Store ID 6792598831 · iOS

Tristimulus is a rigorous color-science bench for people who work with color for a living — colorists, print and brand designers, photographers, and vision researchers. It replaces a pile of scattered web tools with one precise, on-device instrument. Everything is computed locally from bundled reference data; nothing is uploaded and no account is required.

Convert Across Color Spaces

Enter any color and read it instantly across sRGB, Rec.709, Adobe RGB (1998), Display P3 and Rec.2020, alongside CIE XYZ, xyY, L*a*b*, LCh(ab) and L*u*v*. Per-space gamut flags show you exactly where a color clips. See the correlated color temperature and the nearest named color from the bundled dictionaries.

Measure Color Difference

Compare two colors with ΔE76, ΔE94 and the full CIEDE2000 metric, with a plain-language interpretation and a component breakdown (ΔL, ΔC, Δh). A built-in WCAG 2.1 contrast checker rates AA / AAA / large-text / UI thresholds.

Cie Chromaticity Diagram

An interactive CIE 1931 chromaticity plot rendered from the actual color-matching functions — spectral locus, line of purples, the Planckian (blackbody) locus, and toggleable gamut triangles for sRGB, Adobe RGB, Display P3, DCI-P3 and Rec.2020. Switch between the 1931 2°, 1964 10° and 2015 observers.

Illuminants & White-Point Tools

Browse standard illuminant spectral power distributions (A, C, D50–D75, E, the F fluorescent series and LED sources), see each SPD curve, and read its integrated white point and CCT. Chromatically adapt any color between white points using Bradford, CAT02, Von Kries or XYZ scaling.

Get it. Tristimulus: Color Lab is on the App Store for iPhone and iPad.

Privacy and support

Privacy information for Tristimulus: Color Lab · Support for Tristimulus: Color Lab

Questions: shadowfetchapps@gmail.com

Tristimulus: Color Lab · App Store ID 6792598831 · Published by Shadowfetch · shadowfetch.com